Surround sound speaker systems comprise a number of speakers along with a low-frequency effect (LFE) speaker (subwoofer) that are designed to be placed in designated locations in a room to provide an audio surround effect of 360 degrees sound in the horizontal plane. In most cases, surround sound systems map each source channel to its own speaker. Many different surround sound configurations have been developed with the current standard for most surround sound applications being the 5.1 surround format with 3 front speakers, 2 back speakers and a LFE channel. This is commonly used in cinema, television and consumer applications, and is generally driven by the prescriptive locations required for a traditional multichannel mix.
Relatively strict speaker placement rules are defined for surround systems, such as 60 degrees between the L and R channels with the center speaker directly in front of the listener and surround channels placed 100-120 degrees from the center channel, with any additional surround speakers distributed evenly between 60 and 150 degrees. A 5.1 surround system is generally limited in its ability to convey 180 degree or similar panoramic sound, so more extensive surround formats have been developed. For example, a 7.1 channel surround is commonly used in large cinemas and adds two additional channels to provide additional left/right surround channels or even additional screen channels. Other surround configurations include 9.1, 10.2, 11.1, 22.2, and others.
In both cinema and home environments, a common problem during setup of surround sound systems is the location of speakers in the room. Different room sizes and dimensions may impose constraints in speaker positioning, and the orientation angle of each of the speakers as well as their relative positions is also important. The advent of advanced audio processing systems, such as Dolby® Atmos™ has introduced the possibility of using many different speakers including height speakers for configurations such as 5.1.2 (5 surround, 1 LFE, and 2 height speakers), 7.1.2, 7.1.4, 9.1.2, and so on. With the ability to support up to 24.1.10 channels in cinema and home theater applications, the number of speakers to be positioned and oriented can be quite high. This imposes a significant setup burden for users and can result in non-optimal placement of speakers.
To enhance the usability of newer generation surround sound systems, what is needed is a method to allow a user to easily place speakers in a multi-speaker audio system that allows for relatively arbitrary placement of the speakers, and for the automatic discovery (autodiscovery) of speakers in the system.
The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be inventions. Dolby Atmos, Dolby Digital Plus, Dolby TrueHD, and Dolby Pulse are trademarks of Dolby Laboratories.
For purposes of the present description, the following terms have the associated meanings: the term “channel” means an audio signal plus metadata in which the position is coded as a channel identifier, e.g., left-front or right-top surround; “channel-based audio” is audio formatted for playback through a pre-defined set of speaker zones with associated nominal locations, e.g., 5.1, 7.1, and so on (i.e., a collection of channels as just defined); the term “object” means one or more audio channels with a parametric source description, such as apparent source position (e.g., 3D coordinates), apparent source width, etc.; “object-based audio” means a collection of objects as just defined; and “immersive audio,” “spatial audio,” or “adaptive audio” means channel-based and object or object-based audio signals plus metadata that renders the audio signals based on the playback environment using an audio stream plus metadata in which the position is coded as a 3D position in space; and “listening environment” means any open, partially enclosed, or fully enclosed area, such as a room that can be used for playback of audio content alone or with video or other content, and can be embodied in a home, cinema, theater, auditorium, studio, game console, and the like. Such an area may have one or more surfaces disposed therein, such as walls or baffles that can directly or diffusely reflect sound waves. The term “driver” means a single electroacoustic transducer that produces sound in response to an electrical audio input signal. The term “speaker” or “loudspeaker” means one or more drivers in a unitary enclosure, and the terms “cabinet” or “housing” mean the unitary enclosure that encloses one or more drivers. The terms “speaker feed” or “speaker feeds” may mean an audio signal sent from an audio renderer to a speaker for sound playback through one or more drivers.